Sorry for the dual post... bu last time it happened, I tried to get rid of one and it erased both! Can't face typing all that again.

I tried it from bits & pieces and it worked very well...am sure many other ppl did it before and after.

I don't think there is ..."one-stop-shopping thread/post on this topic?"...here...Al described it few times (maybe that's bits&pieces you are referring to?)

Gardenweb/Houzz is one technologically challenged website. I just wasted more than half an hour typing this long post with pictures and it just vanished. I will start again but this time I will be doing it in "bits and pieces".

Last year I did several air layers around mid June and here is a chronicle for one of them - Japanese Maple.

The first pic is of the banding that I did sometime in spring of last year. It is an electrical tape with rooting hormone. The tape is wrapped tightly with sticky side out. Do not want that glue on the bark. Then it was wrapped with foil too. This step is only to increase the chance of air layer being successful. Basically it encourages and preps the branch to form roots. The air layer cuts will be done just below this portion. This picture was taken when I was ready to do the air layer.

After taking the tape out. You can see the discolouration because of lack of light. For very dark bark it may not be as noticeable.

Thank god this time it did not vanish away. So here is more.

Now with a very very sharp blade make two circular incision about an inch apart. I made the top incision in the middle of the banded area. I should have done it even lower. You press the blade and let it bite into the bark and you will a resistance within a mm or two. Roll the blade around in a neat circle as much as possible. Make a vertical slit connecting the two circular incisions and peel of the bark along with the cambium. If you still see green left behind then scrape it off till it is just the white part left. Clean the upper cut again by taking thin slice of the bark plus cambium all around. You want a super clean edge on the upper cut where roots will form.

Then put a zip tie just below the upper cut for good measure. The tissue in the upper cut will start callousing and this will prevent it from bridging the gap.Sometimes I will add a second zip tie below the first one.

Taking no chances. Submit it is.

Huh. vanished again. Third try.

Sprinkle some rooting hormone on the upper part above the zip tie. Then the whole cut area is wrapped with moist soil mix. Pure sphagnum moss is what is usually recommended. I use 511 mixed with some sphagnum moss. Sphagnum moss has some anti-bacterial/fungal properties that is helpful. Here the idea is to have the mix sit snug against the cut and overlap both sides by at least an inch.

It is frustrating step. You will have wrap the plastic with the mix in it. I usually will get it semi wrapped and tie a zip tie at the bottom and some tape to hold it in place. Then use more tape or saran wrap to tighten the soil ball so that it it is snug against the branch. Then finally tie the upper end. You can cover with foil if the air layer is going to exposed to Sun.

After about a month start checking for signs of roots. Some root pretty quick - within a month or so. This one I separated after three months. Started mid June and separated mid Sept.

All trimmed and potted up. The root ball is tied to the pot with wires. You can see some signs of it in the next pic. The roots are fragile and you do not want the plant to move around or knocked over.

This is how I tie the plant to the pot. I attach four wires. Two holes to hold each wire to the pot.

Some notes:

I have only done this for mature hardened branches with bark. Never on a green immature stem. Probably it may still work. I have not yet tried tourniquet method except for ground layering.

Try to select a branch that is more or less vertical. Otherwise roots will develop only on the side facing the ground.

If water starts pooling inside the plastic poke some holes to let it drain out. I usually poke a couple of holes anyway.

Ants love this thing. Check weekly for ants. To deter ants I tie two tapes on both sides with sticky side out.

And just for fun here is a Crape Myrtle I did last year. For this one I gently bare rooted it and planted in gritty mix.

Hope all of this helpful in some way.

Thorough explanation - good job, ToC.

Al

Thanks a lot Al. For a change I had tried to take pictures more regularly and had a story to tell. I do have questions for you regarding pruning the maple but I should start a separate thread on that.

An additional note regarding my comment about ants liking air layers. In one case I found that ants sacrificed themselves on the sticky tape and formed a bridge for the rest to cross. So that does not always work reliably.

Second thing to note is that notice in my pictures the wire is tied around the base of the new stem since the roots were not strong enough to tie them down. That noose will be taken off at the earliest opportunity - probably this season - once I am sure the plant is well anchored in its new home.

I did exactly same as TC so well described and photographed. Didn't use zip tie (didn't know I could!) but will if doing it again. And I used only sphagnum that time. I did it on Ficus Benjamina - that may root faster than Japanese maple?

Here is photo of the root ball - Sept. 3/2012:

Another branch, just unwrapped - I cut off more of the stem below the roots - that's just how much I cut off the tree after rooting:

Looks great Rina. Pretty dense roots. Ficus root much faster. I think I should have air layered earlier than June. Perhaps in May.

TC

I wonder if it is just because it is ficus...I never tried Jap. maple...

Wow, thanks so much!!! This is very helpful and I will study it. I had no idea that the branch needs to be made vertical -- I would never have thought of that.

And Tropic of Cancer, thanks for sticking with the hazards of posting!! I know how frustrating it can be! Rina, your photos are lovely too!! It's very inspiring.

So just to make sure I understand... I don't need the rooting powder during the banding with tape -- the banding is just to block the light which makes the plant more receptive to rooting? (For some reason, I thought I saw where you could put rooting hormone on under the tape?)

And then I cut right below where the band was?

Thanks again for all the help!!

It's not absolutely necessary the branch you're layering is oriented vertically in order to root successfully, it's just a way to help ensure even concentrations of auxin at the proximal end of the cutting, which tends to produce a more even root system that has roots radiating horizontally from the very base of the cutting. When more experienced bonsai practitioners are selecting nursery stock as potensai (potential bonsai), o/a vitality of the plant and what the surface roots look like are the most important considerations. At its essence, it can easily be said that you should choose nursery stock based on whatever tree in the lot needs the least amount of root work. When starting with such young stock in a 1-2 gallon nursery can, it really IS very easy to build your tree in whatever style that currently trips your trigger.

Al

Al wrote: FWIW - when ringing the bark below the point at which you want roots to
form, there is no real advantage when you include the the zip ties.
You'll get the same accumulation of photosynthate and auxin in tissues
immediately above the upper ring cut whether or not you use a
tourniquet.

Actually, my target was to deter the newly forming callous to bridge the gap. Although I am not sure if it helps in this regard at all. I tried the same technique on a different JM - Nishiki Gawa that we have in the ground. It did not root. When I checked this spring the callous had managed to roll over the zip tie but did not bridge the gap completely. So this year I cleaned it up again and started all over at the same spot. I think this is a hard variety to root.

N2SG: A light sprinkling of rooting hormone under the band is helpful. For easy to root ones you can skip the banding step. I do not know whether Roses root easily. I am guessing they are not that difficult plants.

Al

Thank you for the info on roots forming...